Canizares played his final four holes at the Pelican Marsh Country Club in four-under-par to grab a one-shot lead over Dana Quigley and Mike McCullough, who eagled the par-four seventh.
Hugh Baiocchi, John Bland, Bruce Summerhays and Jim Ahern are all tied for fourth place at two-under-par, two shots off the lead.
In three full seasons on Tour, Canizares has four runner-up finishes, three of which have come in playoff losses. One of those sudden-death defeats came last year at this tournament. Canizares held a share of the 36-hole lead, yet lost to Lanny Wadkins, who fired a final-round 64, on the third extra hole when he hit his second shot into the water.
Friday, the 53-year-old Spaniard birdied his first two holes, but gave both strokes back with bogeys at the fifth and 11th holes.
Even par through 14 holes, Canizares birdied the par-four 15th, eagled the par-five 16th, and then birdied the par-four finishing hole for a round of four-under-par 68.
Quigley was four-under-par through 17 holes, but dropped his approach shot at the par-four 18th into the water guarding a tucked pin. Quigley, playing in 118th consecutive Senior Tour event, managed to salvage a bogey for a round of three-under 69.
'I was leaking a bit of oil on the last few holes, but somehow luck prevailed,' Quigley said. 'As you can see, I hit it all over the map, but my wedge saved me.'
Quigley only hit 11 of 18 greens in regulation in the first round, but chipped in for birdie twice at the 10th and 17th holes.
Larry Nelson, who has won both official events played in 2001, is four shots off the pace following a round of even-par 72. Defending champion Lanny Wadkins is six back of Canizares, tied with Gary Player and Bruce Fleisher at two-over.
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